If $x \otimes y = xy+3x-y$ and $x \triangleleft y = 4x-3$, find $1 \triangleleft (-5 \otimes 4)$.
Solution: We don't need to find $-5 \otimes 4$ because $x \triangleleft y$ depends only on the left operand. Find $1 \triangleleft y$ $ 1 \triangleleft y = (4)(1)-3$ $ \hphantom{1 \triangleleft y} = 1$.